Currently the concurrent marker visits any fixed array in one go
ignoring the progress bar and does not expect seeing black arrays
in the worklist. For this reason, if the main thread marker starts
visiting a large array with the progress bar, then it has to re-push
the array in the bailout worklist. So all subsequent visitations of
the array happen on the main thread.

This patch makes the progress bar thread-safe and allows the
concurrent marker to visit arrays in chunks.

Change-Id: I5e8867077ed2908b7f9c5d8bde34d0401f7fe446
Reviewed-on: https://chromium-review.googlesource.com/c/1385164
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58484}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/7f37dc1..70cbac6

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: I977ef05a0473602d831afd15de9a298bff9fb0de
Reviewed-on: https://chromium-review.googlesource.com/c/1390931Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#58483}

BUG=chromium:917136

Change-Id: I02696a3315c22b34705bbc48cddaeb9e6c59fa9f
Reviewed-on: https://chromium-review.googlesource.com/c/1391749Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58482}

This reverts commit 0fbe2717.

Reason for revert: Debug data has been collected. Removing debug code.

Original change's description:
> [inspector] Add extra debug code to investigate crbug/897816
> 
> BUG=chromium:897816
> 
> Change-Id: Ie28efcab73ccbcb6d8b1a7508b99aec59f3a3ae3
> Reviewed-on: https://chromium-review.googlesource.com/c/1384795
> Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
> Commit-Queue: Alexei Filippov <alph@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58383}

TBR=dgozman@chromium.org,alph@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: chromium:897816
Change-Id: I6b2b5dae2b7e42843d72573ba598e5acfec3514b
Reviewed-on: https://chromium-review.googlesource.com/c/1390926Reviewed-by: Alexei Filippov <alph@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58481}

Prevent aliasing between problematic registers for
shift operations with int64 values in the arm port
of Liftoff.

Bug: v8:6600, chromium:912592
Change-Id: I905f0a657626fdfac3e41fe2878e918e3c779a8f
Reviewed-on: https://chromium-review.googlesource.com/c/1388564
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58480}

They will later be detected as redundant again, but we can save memory
and performance by just not adding them in the first place.

R=mvstanton@chromium.org

Bug: v8:8423
Change-Id: I11d88642333681612e2f8f4eaee7ba700cbf64d5
Reviewed-on: https://chromium-review.googlesource.com/c/1390132Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58479}

This silences the new presubmit check for all base classes.

R=tebbi@chromium.org

Bug: v8:8616
Change-Id: I389fedde1b44d9c583dd2fb75e6c8af138c4feb0
Reviewed-on: https://chromium-review.googlesource.com/c/1387491
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58478}

Bug: v8:8616
Change-Id: I2774bf86b3446afddb7cf269e88ba128e53ae7f6
Reviewed-on: https://chromium-review.googlesource.com/c/1390130Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58477}

Bug: v8:7703
Change-Id: I2cc5ceb7b70a9b53d5bcc90b32276c011f89ffbe
Reviewed-on: https://chromium-review.googlesource.com/c/1388530
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58476}

This reverts commit 2d2c1374.

Reason for revert: layout test timeout - crbug.com/917714

Original change's description:
> Reland^2 "[turbofan] Use feedback when reducing global loads/stores."
> 
> This reverts commit ac85ab0a. A
> chromium test caused trouble and was taken care of in
> https://chromium-review.googlesource.com/c/1384064.
> 
> Original change's description:
> > [turbofan] Use feedback when reducing global loads/stores.
> >
> > We already record the script context location or the property cell
> > as feedback of the global load/store IC, so Turbofan doesn't need
> > to do the lookups again.
> 
> TBR=sigurds@chromium.org
> 
> Change-Id: I58bcd9bceec2f9cf401f7b0fc4460a6da6cd0abc
> Reviewed-on: https://chromium-review.googlesource.com/c/1386404
> Commit-Queue: Georg Neis <neis@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58393}

TBR=neis@chromium.org,sigurds@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I9003135cfc5cc3ffb8bbf06ca35c9773adac93e7
Reviewed-on: https://chromium-review.googlesource.com/c/1390129Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58475}

Bug: v8:8477, v8:8562
Change-Id: Id97f5b53fe6e6a696d8955acc1ab1bc5ac2f4052
Reviewed-on: https://chromium-review.googlesource.com/c/1388527
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58474}

Bug: v8:8477, v8:8562
Change-Id: I54b857cdacf9360b95d64147a486a0d5fa1ffe10
Reviewed-on: https://chromium-review.googlesource.com/c/1388526
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58473}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/b71c9cc..7f37dc1

Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/2cf76f5..106695b

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: I661f882c0add60d4e667577a99c92b3f068b6756
Reviewed-on: https://chromium-review.googlesource.com/c/1390919Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#58472}

Bug: v8:8477, v8:8562
Change-Id: I6ef4291ebd6c2bb6acc4b525014ec02a88d45281
Reviewed-on: https://chromium-review.googlesource.com/c/1388525
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58471}

Tbr: ahaas@chromium.org,leszeks@chromium.org,verwaest@chromium.org
Bug: v8:3770
Change-Id: Ia6530fbb70dac05e9972283781c3550d8b50e1eb
Reviewed-on: https://chromium-review.googlesource.com/c/1390116
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Alexei Filippov <alph@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58470}

This reverts commit 97628eee.

Reason for revert: breaks compilation in Lite mode, which does not allow overriding of certain flags. See https://logs.chromium.org/logs/v8/buildbucket/cr-buildbucket.appspot.com/8926078411629093216/+/steps/build/0/steps/compile/0/stdout.

Original change's description:
> [error] extend error stack w/ function parameters
> 
> Extend FrameArray to hold weak references to parameters for functions in
> the call stack. The goal here is to provide more metadata for postmortem
> tools (such as llnode), especially in cases of rethrowing (this will be
> particularly useful when using postmortem with promises on Node.js).
> 
> Besides postmortem, these changes allow us to print a more detailed
> stack trace for errors with parameters types (or even values), which can
> be useful since JavaScript functions can receive any number of
> parameters of any type, and having a function behave differently
> according to the number of parameters received as well as their types is
> a common pattern on JS libraries and frameworks.
> 
> R=​bmeurer@google.com, yangguo@google.com
> 
> Change-Id: Idf0984d0dbac16041f11d738d4b1c095a8eecd61
> Reviewed-on: https://chromium-review.googlesource.com/c/1289489
> Commit-Queue: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58468}

TBR=yangguo@chromium.org,bmeurer@google.com,bmeurer@chromium.org,mat@mmarchini.me

Change-Id: Ide0a434c1521ab2bbeca6821397ff63ba7d40fe5
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/1390128Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58469}

Extend FrameArray to hold weak references to parameters for functions in
the call stack. The goal here is to provide more metadata for postmortem
tools (such as llnode), especially in cases of rethrowing (this will be
particularly useful when using postmortem with promises on Node.js).

Besides postmortem, these changes allow us to print a more detailed
stack trace for errors with parameters types (or even values), which can
be useful since JavaScript functions can receive any number of
parameters of any type, and having a function behave differently
according to the number of parameters received as well as their types is
a common pattern on JS libraries and frameworks.

R=bmeurer@google.com, yangguo@google.com

Change-Id: Idf0984d0dbac16041f11d738d4b1c095a8eecd61
Reviewed-on: https://chromium-review.googlesource.com/c/1289489
Commit-Queue: Yang Guo <yangguo@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58468}

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/7c1d51b..a923c2a

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: Ia5e0c5e98c1d3086a5d5b461fe3e9d0b86842def
Reviewed-on: https://chromium-review.googlesource.com/c/1390915Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#58467}

The concurrent marker can now visit maps and mark the subset of
descriptors that a map requires.

Bug: v8:8486
Change-Id: I184442ec90a8f60c73cfe16d6e9d66f4efa92a01
Reviewed-on: https://chromium-review.googlesource.com/c/1384320
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58466}

Factory::NewRawOneByteString initializes the string length without
atomic accessor. This leads to data race if the string is pretenured
and black allocated because the concurrent marker loads the string
length before checking the string markbits.

This patch changes the order to check the markbits first.

Bug: v8:8579
Change-Id: Ic434f7dde9baa6264fe133499d2394c0d4cc5394
Reviewed-on: https://chromium-review.googlesource.com/c/1388542
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58465}

Bug: v8:8521
Change-Id: I6e02930108ba90adf6d54aca319d2d2680964860
Reviewed-on: https://chromium-review.googlesource.com/c/1388543
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58464}

Logic is added to InterpreterEntryTrampoline to detect flushed functions,
and enter CompileLazy instead. Get the bytecode array from the function
object and load it. The bytecode array could have been flushed from the
shared function info, if so, call into CompileLazy.

This fixes:

   cctest/test-heap/TestBytecodeFlushing
   cctest/test-heap/TestOptimizeAfterBytecodeFlushingCandidate
   debugger/debug/lazy-deopt-then-flush-bytecode

[mips] Macro-assembler fix

Fix massive failing of tests after fa3cbf60.

Change-Id: Ic1978b5233eefc743fd7b020f65153630ffa281f
Reviewed-on: https://chromium-review.googlesource.com/c/1388528Reviewed-by: Sreten Kovacevic <skovacevic@wavecomp.com>
Commit-Queue: Sreten Kovacevic <skovacevic@wavecomp.com>
Cr-Commit-Position: refs/heads/master@{#58463}

Change-Id: Ic156eefa7ee2de568a368c44eca0ba80ab8828b0
Reviewed-on: https://chromium-review.googlesource.com/c/1388567Reviewed-by: Sreten Kovacevic <skovacevic@wavecomp.com>
Commit-Queue: Sreten Kovacevic <skovacevic@wavecomp.com>
Cr-Commit-Position: refs/heads/master@{#58462}

These test off-heap builtin call sequences and don't make sense in
noembed builds.

Tbr: sigurds@chromium.org
Bug: v8:7777
Change-Id: I2795257e33b6ad87958d08f0845b75a7e88988f2
Reviewed-on: https://chromium-review.googlesource.com/c/1390120Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58461}

This reverts commit 28275cd4.

Reason for revert: Ho ho.. oh :{

Original change's description:
> Seasonal greetings
> 
> Ho ho ho.
> 
> Tbr: santa@chromium.org
> No-presubmit: true
> Change-Id: Ida950937a352f32ccf8127907f623e92332f4806
> Reviewed-on: https://chromium-review.googlesource.com/c/1390119
> Reviewed-by: Jakob Gruber <jgruber@chromium.org>
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58459}

TBR=jgruber@chromium.org

Change-Id: I2f7d0a92d0af95e814a2d6cb04ceaf445d57023a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/1390121Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58460}

Ho ho ho.

Tbr: santa@chromium.org
No-presubmit: true
Change-Id: Ida950937a352f32ccf8127907f623e92332f4806
Reviewed-on: https://chromium-review.googlesource.com/c/1390119Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58459}

noembed bots have started failing since https://crrev.com/c/1382461.

The reason was that inline_offheap_trampolines option was set to true
even in noembed builds, and the assembler tried to inline trampolines
to non-existent embedded builtins.

Tbr: sigurds@chromium.org
Bug: v8:7777
Change-Id: I483dd8b77269b8684e57f8da6e659a9648b1657b
Reviewed-on: https://chromium-review.googlesource.com/c/1390117
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58458}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/ce4fbca..b71c9cc

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: I2c256e47641ea1e5cd1b4496329ecb4f5842076e
Reviewed-on: https://chromium-review.googlesource.com/c/1390200Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#58457}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/b360239..ce4fbca

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/d7d7892..7c1d51b

Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/2e63407..2cf76f5

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: I7e89de601758ee51241e6266f4f8b25437026337
Reviewed-on: https://chromium-review.googlesource.com/c/1390197Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#58456}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/b61a4fb..b360239

Rolling v8/buildtools: https://chromium.googlesource.com/chromium/buildtools/+log/0e1cbc4..7d88270

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/2f6c18c..d7d7892

Rolling v8/third_party/depot_tools: https://chromium.googlesource.com/chromium/tools/depot_tools/+log/58649e3..db0055d

Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/4685377..2e63407

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: I2a4c071fb173e4eb124037d8c4699f65fc79435b
Reviewed-on: https://chromium-review.googlesource.com/c/1389775Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#58455}

- Removes ModuleCompiledCallback typedef and Set function.
- Adds WasmStreaming::Client abstraction and Set function.

Bug: chromium:719172
Change-Id: I8a207b628394a7660bda73cde560da1e461248a7
Reviewed-on: https://chromium-review.googlesource.com/c/1377450Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58454}

Presumably this was obsoleted when this functionality moved to
the BytecodeGenerator.

Change-Id: I691fdaa01610ea050511825b5ad1f3ba4963421c
Reviewed-on: https://chromium-review.googlesource.com/c/1387991Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58453}

Change-Id: Id4f99539b8583cef56fd33d2e939a2d6024384f9
Reviewed-on: https://chromium-review.googlesource.com/c/1387989Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58452}

A computed property can never be a private field. That's a SyntaxError.

Change the check to a DCHECK.

Bug: v8:5368
Change-Id: I6701b60f3193639f3ccffacda25074d32d5de5b8
Reviewed-on: https://chromium-review.googlesource.com/c/1385267Reviewed-by: Mythri Alle <mythria@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58451}

Change-Id: I8292b10afd2494199b5db11a5e3d64912cff919b
Reviewed-on: https://chromium-review.googlesource.com/c/1387988Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58450}

NATIVE_CONTEXT_IMPORTED_FIELDS are no longer different from other
NATIVE_CONTEXT_FIELDS, so this CL joins them together.

While doing so, removed the OBJECT_VALUE_OF slot, which is not
referenced anywhere.

Change-Id: I79c46e6e6cc92c90e90e68165cf7b0ae31e8151d
Reviewed-on: https://chromium-review.googlesource.com/c/1387631Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58449}

%AddNamedProperty was only used by regression tests, and is easily
replaced by Object.defineProperty (or deleted, in the case of a
cctest that was designed to test it directly).

%AddElement was unused (probably due to the death of array.js).

Bug: v8:7624
Change-Id: Icc17fd7a7419aa649275414a351f176f104040e2
Reviewed-on: https://chromium-review.googlesource.com/c/1387990Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58448}

Change-Id: I8283ddf96dc178f12e52d9412db1858acfe46650
Reviewed-on: https://chromium-review.googlesource.com/c/1387966Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58447}

This reverts commit 3411e7c3.

Reason for revert: Breaks test expecations - https://ci.chromium.org/p/chromium/builders/luci.chromium.try/linux_chromium_rel_ng/260731

Original change's description:
> [parser] Create arrow function scopes while parsing the head
> 
> This simplifies NextArrowFunctionInfo, allows us to Scope::Snapshot::Reparent
> directly rather than moving it, and allows us to skip reparenting in the simple
> parameter arrow function cases.
> 
> This CL additionally fixes arrow function name inferring.
> 
> Change-Id: Ie3e5ea778f3d7b84b2a10d4f4ff73931cfc9384a
> Reviewed-on: https://chromium-review.googlesource.com/c/1386147
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58405}

TBR=ishell@chromium.org,verwaest@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I8f31b96f844f0673364bf435fa6c809e40d62fa3
Reviewed-on: https://chromium-review.googlesource.com/c/1388541Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58446}

Always pass in the target scope for the body, and check whether we're in
LexicalVariableMode instead to distinguish for(let/const from for(var.

Change-Id: Idf59423466f45eebe7c9d716f8eb6ccd92235abc
Reviewed-on: https://chromium-review.googlesource.com/c/1388534Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58445}